another vote for Southern Pines/Vass.
I moved to the area for a 3-year job, and fell in love so we bought a farm and now call NC our forever home.
We have lots of good venues for schooling and rated shows, and NC state vet school is great for emergencies. Since there are SO many horses in the area, we have a ton of options for vets, farriers, bodywork, etc, so you can find someone who practices the style you want. There are several options for good H/J trainers, and you can align with someone serious who does FL all winter, or stays home and shows in NC/SC/VA on weekends, or just does the very local circuit. Again, due to density, there are just lot of choices.
It’s hot and humid in the summer, but if you get up early and finish riding by 11am, you’re fine. The ‘Sandhills’ really is sandy, so we don’t have mud. The Walthor Moss foundation has thousands of acres of trails, open and free of charge to all horses ridden/driven, as well as a hunter trial field where you can go school log jumps, coops, small banks, etc. It truly is Mecca, though as others have said, costs of horse keeping may surprise you if you’re coming from, say, the midwest. The biggest expense is hay, since the local "coastal bermuda’ carries increased colic risk, so most of us pay more for T/O/A shipped from up north or out west. Join the “Sandhills Equestrians” page on FB, where there are lots of posts about boarding options, events, etc.
And Southern Pines/Pinehurst/Whispering Pines has a zillion golf courses and hosts the US Open every few years.